Had the same problem today, after package updates. This as also happen previously.
Fixed by typing xfwm4 into the terminal. ** Attachment added: ".xsession-errors" https://bugs.launchpad.net/ubuntu/+source/xfwm4/+bug/495361/+attachment/2441446/+files/.xsession-errors -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/495361 Title: [Xubuntu] No window manager at startup To manage notifications about this bug go to: https://bugs.launchpad.net/metacity/+bug/495361/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs